Vibratory system



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Nov..l1, 1930. A. L. THURAS VIBRATORY SYSTEM Filed March 26, 1926 Patented Nov. 11, 1930 1 UNITED STATES PATENT OFFICE ALBERT L. THURAS, OF EAST ORANGE, NEW JERSEY, ASSIGNOR T0 BELL TELEPHONE LABORATORIES, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK VIBRATORY SYSTEM Applicationfiled March 26, 1926. Serial No. 97,608.

V 5 The primary object of the invention is to provide for the faithful transmission of vibrations without distortion or the introduction of undesirable foreign vibrations.

Another object of the invention is to provide for the-"return of the vibratory element to a neutral position as soon as the actuating influence ceases. 1

In carrying the invention into practice the vibratory elementis so mounted thatit is free It to oscillate in one plane about a given axis,

butis heldagainst movement in any other direction, it also being understood that bodily movement of the vibratory element in any direction is likewise overcome. Furthermore, the mounting is such as to eliminate all pivots and like structures which, through wear or lack of maintenance, are apt to become loose and createdistortion. V

Illustrative of a specific aspect of the invention the vibratory element is represented by the stylus bar of a reproducer such as is in common use onphonographs and the like. Oneend of the stylus bar carries the usual stylus for contact with a sound record while the opposite end is secured to the diaphragm of the reproducer. The stylus baris fixed intermediate its ends to a torsion member, commonly known as a reed, the ends of which are secured to the body of the reproducer so that the stylus bar is firmly supported, yet easilyloscillated in one direction. In order to further support and brace the reed, and to prevent bodily movement of the stylus bar in the plane of its oscillation, tension, or tie, members are secured to opposite sides of the reed on each side of the stylus bar. These tension, or tie, members are arranged in a plane with the longitudinal axis of the reed and their opposite ends are fixed, as are the ends of the reed. ,It will thus be apparent can that any tendency of the reed to bow and bodily move the stylus bar toward or away from the diaphragm will be overcome. It will also be evident that the stylus bar will be yieldably held in neutral position by the resilience of the reed and tension members which resilience acts to maintain the diaphragm in proper position and overcome any distortion thereof.

The invention may be more clearly understood by reference to the accompanying drawing, in which, i

Fig. 1 is a side view of a reproducer equipped with a stylus bar mounted in accordance with this invention,

Fig. 2 is a sectional View taken on line 2- -2 of Fig. 1,

Fig.3 is a perspective view of a stylus bar showing the same assembled on a reed embodyingthis invention, and

m Fig. 4 is a perspective view of one supporting means for the stylus mounting shown in Fi 3 Referring to the drawings in detail the lmproved stylus mounting, comprises a torsion member or reed 7 of springsteel or other suitable material intermediate of the ends of t which the vibratory element 8, commonly referred to as a stylus bar, is rigidly mounted. The reed 7 may be secured to the vibratory element 8 by electro-welding, silver soldering or by any other suitable method. Secured in a similar manner to. opposite sides of the torsion member 7, on opposite sides of the vibratory element 8, are tension, or tie, members 9 of spring steel or suitable spring material. The tension, or tie, members 9 lie in one plane which, in the structure shown, is perpendicular to the plane of the torsion membenand intersects it along the line of the axis of oscillation of the stylus bar. The ends of the torsion member and the outer ends of the tension members are rigidly held in thestylus mounting supporting means to be more fully described hereinafter.

' The stylus mounting supporting means is designated generically by the numeral and comprises a stationary plate 11 which is rigidly associated with a reproducer 12..-The plate 11 is provided intermediate its ends with a recess 13 which opens outwardly through one edge and receives a clamping block 1 1.. Formed at opposite ends of the stationary plate 11 are parallel'arms 15 which extend outwardly from one side oisaidplate as clearly shown'inFigure 4.

Cooperating with the stationary plate 11 is a clamping plate 16, which like the plate ll'i'sformed intermediate. its ends with arecess 17 whicliopens outwardly through one edge and receives the clamping block 18. The

' plate 16 is provided at its opposite endswith. laterally extending parallel arms 19 which are retained in abutting engagementwith' the rob ends of the arms 15 by means of suitable attaching devices such as screws 20. a

' Clamped betweenthe abutting ends of'the arms 15' and 19 is the torsion member or'reed 7 while the outer ends of the tension members 9 are received in the recesses 13 and 17 and are retained against the inner wall therecillation.

of by means of the clamping blocks 14 and It will thus be seen that the parts are securely held inproperposition at all times and danger of'the device gettingout ofadjust ment isv minimized, owing to the elimination of pivots. The lateral bracing of the torsion member 7, by the tensionmembers 9, overcomes any bowing tendency of saidtorsion member and consequent bodily'movement of the vibratory element 8 in the plane of its os- 7 Furthermore, "it will be obvious that as the torsion member 7' is flexed, the tension members 9 are put understressand will aid the torsion member in'returning-the vibratory element to its normal position Thus it will be seen that the opportunitiesfor the diaphragm tobecome distorted" are re-' duced to the minimum without in any way hampering the tree oscillation of the vibratory element.

thereof and meansfor rigidly What is claimed is V Y i 1. Amounting for a vibratory element com- .prising a torsion member and tension members extending from opposite sides of said torsion member to' prevent lateral deflection supporting one end of each tension. member; 2. A mountingfor a vibratoryelement com- "prising a torsion member, and tensionmembers secured to and extending from opposite sides of the torsion memberina plane with its longitudinalaxis. v

3. A mounting for avibratory element comprising a torsion membe-ririgidly supported at opposite ends, and tension members secured to and extending from opposite sides of the torsion member in a plane with its longitud '1 ax s.

tension member.

4. A mounting for a vibratory elementcomprising a torsion member, tension members secured to and extending from opposite sides of the torsion member in a; plane With'its longitudinal axis, and supporting means for the outer ends of the tension members.

' 5. A mounting for a vibratory element com-. prising a torsion memben'means rigidly supporting the ends of the torsion niember,'tension members extending from opposite sides of; the torsion member, and means rigidly supporting the ends of the tension members.

(SQA fiexiblemount-ing comprising a tersion memb r, fmeans rigidly; supportingjthe ends thereon;- ayibrat'orygelement supported intermediate the ends of the torsion inen ber,

.1tensi0n; members secured to oppositefaces of the torsion member, and means rigidly supporting tl ie endsrofi the tension members.

7. A flexible mounting comprising artor sion member, means rigidly supporting the ends thereof, avibratory element supported intermediate the ends of the torsion member,

tension members secured to opposite faces of rigidly supporting the opposite ends of ea-qh 9.; A .mounting for a vibratory-element comprising a thin flat torsion member, ex

tendinglaterally from each sid'eo-f said "eie-u 'ment, said torsion memberbeing inflexible in its own plane, and. a plurality, of thin flattension members on each side otsaidtorsion Tmeinber adj 'aeent said I element for prevent- "i' ig transverse movement of said torsion member, theplanes oifsaidtension members interi'secting the plane of said torsion member at the axis of oscillationgof said element-and means :tor'rigidlysupporting one'end ofeach tension member;

' 10. A mo in ting fora vibratory element comprisinga torsion member,' supports to WlllClLllllG ends of sai'dtorsion member are rigidly connected, a. pair-of tensibn-members extending trom one'side ofsaid torsion inemher and a second pair of tension members extending froin'th'e opposite side, "for pre- Venting transverseinovementfof said torsion member, all of said tension 1 members-lying in the same plane and means fo -rigidly supporting "one endofeach tension'meinber;

11. The combination of adia'phragima vi- I bratory element anda mounting for sa idel'e- "ment comprising a thin fia ttersionn'iernber lying in a plane parallel to the planeof sa id diaphragm, supports for the ends of said torsion member, a plurality of tension members lying in a plane at right angles to theplane of the diaphragm and extending from the opposite sides of said torsion member for preventing transverse deflections thereof and means for rigidly supporting the opposite ends of each tension member.

In witness whereof, I hereunto subscribe my name this 22 day of March, A. D. 1926.

ALBERT L. THURAS. 

